The Inversion Principle in Health and Fitness

With the Cardiff Half Marathon having just taken place this past weekend, it reminded me of an interesting interaction from a few years ago now. A client-friend had approached me having taking up running ahead of completing the “Half” back in 2018. They had some experience prior with running but never consistently, and rarely longer than a 5km Park Run.

Eager to make some rapid early progress, they’d done a quick Google search and downloaded a Half Marathon programme without too much thought and got started. By Week 4, I had a WhatsApp message describing a potential knee injury that was limiting to them to barely a few kilometres without a shooting pain that wasn’t resolving with rest. I’d asked them to forward across the plan they were following and share any of the Garmin data they’d collected so far prior to meeting in person.

Week 1 - 26 miles per week.

Week 2 - 31 miles per week (knee starting to niggle…)

Week 3 - 34 miles per week (having to apply ice after each run, sore between sessions…)

Week 4 - 6 miles (at the point of missing or stopping runs early…)

It was clear just from these first few weeks, this was way too much mileage for where the individual was starting from, this was an intermediate level if not early-stage advanced amount of running volume this early into a programme.

When we met in-person, they were clearly disheartened, frustrated, and considering abandoning the Half Marathon attempt altogether with now only 12-weeks to go.

Our first point of discussion was the programme selection.

Coach: “So prior to signing up, how often/far were you running?”

Client: “I wasn’t really, maybe 10 or so kilometres a week at most…”

Coach: “When searching for the programme, did you have a finish time in mind?”

Client: “No, not really. I just didn’t want to follow a beginners’ programme, I don’t see myself as a beginner as I’m still active.”

We’d hit the nail on the head within the first 5 minutes of conversation.

They’d made the programming decision based on chasing swift improvements, rather than focusing first on what was sustainable and unlikely to lead to injury for where they were starting from now.

We often set our sights primarily on what we want to achieve - a faster mile, a heavier lift, a slimmer waistline. While goals are no doubt important, with something like training for a Half-Marathon or Marathon, when the time horizon can often be 12-18 weeks (if not longer…), it’s often far wiser an approach to consider first what we don’twant to occur, than what we do. By identifying and avoiding potential pitfalls like injury, burnout or demotivation, all of which the client in question was feeling at the time, we’re far more likely to create a sustainable path to eventual success.

This idea of the inversion principle, a mental model that involves focusing on what you want to avoid, rather than solely on what you want to achieve, isn’t something new.

Much like my client’s hasty approach to picking up running, investors who chase gains without managing risks often find themselves facing setbacks. Seasoned professionals often prioritise avoiding loss first and foremost, rather than chasing massive gains.

The legendary investor Warren Buffet had a famous quote, “Rule number one: never lose money. Rule number two: never forget rule number one”. For anyone familiar with Buffet, he’s one of the richest and most success investors to have existed, and yet it is this incredibly cautious, inverted strategy, recognising that preserving capital is fundamental, that contributed to his billions made over an incredibly successful career. After all, recovery from a significant loss requires a disproportionately larger gain than simply not suffering the loss in the first place.

Going back to my client-friend example. By rushing into an intermediate programme without significant research and pre-thought, they now faced a 3-6 week delay in training to deal with an overuse injury that could easily been accounted for, and possibly prevented, by accepting their initial starting point as a “beginner” to this type of training volume.

The next 15-20 minutes of our conversation essentially involved helping the client to flip perspective as to what they needed to actively avoid in reaching the goal.

They needed to significantly reduce the running volume to begin, to enable whatever was happening with the knee to be clearly diagnosed by a physio/medical professional to see the extent. We then needed to develop a running programme that met the individual where they were start from now, not some perceived reality of fitness that they wish they had or were attempting to reach.

In this example, once cleared that there was no chronic issue with the knee, we pulled the running frequency back from 5 sessions per week, back to 3 sessions to enable 24-48hrs recovery between to start. It then mean’t logically and systematically increasing volume and intensity based on the feedback both objective, through their Garmin Watch, and subjective, based on regular check-ins. Whilst they didn’t reach the intended race finish time, they were incredibly grateful at just being able to finish the race at all considering how close they were to packing it in only four weeks into training.

Applying the mental model of inversion into fitness can be transformative. Instead of fixating solely on ambitious targets and the eventual end-goal, we can also apply focus early on to strategies how to sidestep and prevent obstacles that commonly derail progress.

Injury prevention is always a great example as it tends to be the most overall impactful on halting people in their tracks. Pushing our bodies beyond their limits might yield quicker than average returns in the short term, but it also increases the risk of potential harm in the long run. An injury doesn’t just halt progress; it can in some cases reverse it. By prioritising proper from, running mechanics, adequate rest, and gradual progression, we hope to minimise the risk of setbacks.

It’s not glamorous, and doesn’t offer rapid results, but it’s a strategy that keeps us moving forward consistently.

The enthusiasm at the start of a new fitness journey, like my client-friend had when signing up, and I’m sure a number of individuals who having seen those completing the event on Sunday would have felt, can be powerfully motivating. But it’s also so simple in this early phase to overcommit - daily workouts, strict diets, drastic life changes.

It becomes an all-or-nothing approach, unsustainable for any length of time that’s worthwhile. Eventually the initial excitement wanes, fatigue kicks in, muscles become sore, joints start to ache, and we may find ourselves skipping sessions or abandoning plans completely.

In many ways, avoiding what we don’t want requires a deep introspection. It means acknowledging our vulnerabilities and planning accordingly. It’s not a pessimistic approach but a practical one - recognising that pitfalls do exist, the type of individual you are, and taking proactive steps to avoid them as early in the journey as possible.

The inversion principle is often aligned with the concept of “addition by subtraction”. Sometimes removing habits, behaviours or obstacles can have a more significant impact than adding new elements to our approach. In chess for example, mastering the game isn’t just about advanced tactics; it’s about avoiding the most commonly made mistakes, and limiting first and foremost the errors in play that you make.

“Rule number one: never lose money.”

Applying this principle into fitness, we can begin to understand the common reasons why people fail in reaching goals they set for themselves. Unrealistic expectations, lack of consistency, improper technique - by being aware of these pitfalls, we can take steps initially to prevent them. It’s a defensive strategy that strengthens the overall approach.

This doesn’t mean we abandon goal-setting altogether, or stop striving for any form of improvement. Instead, it’s about finding a balance between the two. By coupling our aspirations with a genuine awareness of what could hinder them, we can create a more robust plan for those we’re coaching.

As a side-note, the final question in the IFT Client Onboarding Questionnaire literally asks “What barriers to you see in preventing you from reaching your goal?”. You can often tell how serious an individual is about their goal just by how they respond to this question.

So how can we implement this approach in our fitness journeys?

First, take time to genuinely reflect on your past experiences. Have there been times where you’ve rushed into a fitness goals and become injured, burned out early, or suffered a loss of motivation derailing your progress? What factors contributed to those outcomes? By understanding your history, you can identify patterns to avoid in future.

Second, prioritise education. Knowledge empowers you to make informed decision that minimise risk. Learn the proper techniques, understand the principles of training and recovery, and seek advice when needed.

Third, listen to the feedback your body and mind are giving you. Pain, persistent fatigue, and a lack of overall progress can be signals that something isn’t quite going to plan. Ignoring these signals when they first arise can lead to far bigger problems further down the line.

Lastly, be flexible. If something isn’t working don’t be afraid to adjust your plan. Stubbornly sticking to a failing strategy simply because that what’s written down, or what you’ve been told to do that day, can be far more detrimental than adapting to a new approach either temporarily or long-term.

It’s not as flashy a sales pitch as high-intensity transformations (30 days to…), but it’s a strategy that promotes longevity and well-being.

So next time you’re mapping out a fitness goal, or if you’re already one the hundreds that would have signed up to Cardiff Half Marathon for 2025, consider flipping the script. Ask yourself not just what you want to achieve, but what you need and want to avoid along the way. By recognising and steering clear of the obstacles that commonly trip us up, we increase our chances of success greatly.

After all, sometimes the best way forward is to sidestep the pitfalls along the path.